What Are Pyrethrins and Pyrethroids?
Pyrethrins are insecticides derived from chrysanthemum flowers. They've been used in pest control for decades. Pyrethroids — permethrin, bifenthrin, cypermethrin, and others — are their synthetic cousins, engineered to last longer and hit harder.
Both share one important characteristic: they're broad-spectrum. That means they don't just kill mosquitoes. They kill insects indiscriminately.
And that's the problem.
Broad-Spectrum Means Collateral Damage
When a technician sprays pyrethroids across your yard, the treatment doesn't distinguish between mosquitoes and the other insects living in your landscape.
Bees, butterflies, and other pollinators that land on treated surfaces are at serious risk. Pyrethroids are highly toxic to bees, and given how fragile pollinator populations already are, they serve as a good barometer for the overall environmental impact of a treatment. If the bees can't survive it, the treatment is doing more than controlling mosquitoes.
But it goes beyond pollinators. Pyrethroids also kill beneficial predatory insects — the ladybugs, parasitic wasps, and ground beetles that naturally keep pest populations in check. Wipe those out, and you can actually make your pest problems worse over time. You become more dependent on the spray, not less.
And the impact doesn't stop at your property line. Pyrethroids are extremely toxic to fish and aquatic invertebrates. Runoff from treated yards reaches storm drains, creeks, and watersheds, carrying those chemicals into ecosystems that are especially vulnerable to them.
What About People and Pets?
Pyrethroids are considered lower risk to mammals compared to the older pesticide classes they replaced. But lower risk isn't no risk, especially when you're talking about repeated applications throughout an entire mosquito season.
For most homeowners, the concern isn't acute exposure. You're not going to get sick from walking across a treated lawn. The more relevant question is what happens with ongoing, low-level exposure over months: residue on deck railings and patio furniture, contact with treated turf in play areas, and drift during application.
Emerging research has started to raise questions here. A study published in JAMA Internal Medicine found that a common pyrethroid metabolite was associated with increased cardiovascular mortality risk in the general U.S. adult population — not applicators, but everyday people. Other studies have flagged potential concerns around reproductive health and endocrine disruption. This research is still developing, and we're not here to overstate what the science has settled. But it does raise a fair question: if there's an equally effective option that doesn't invite those questions at all, why not choose it?
For pets, the picture is more clear-cut. Cats cannot properly metabolize pyrethroids — their livers lack the specific enzyme pathway needed to break these compounds down. Even residue-level contact with treated surfaces can trigger serious neurological symptoms in cats, and in severe cases it can be fatal. Dogs are more tolerant, but can still experience skin irritation and neurological reactions. Fish are extremely sensitive and can die from even small amounts of pyrethroid exposure.
When a company sprays pyrethroids across your yard every two weeks, your pets are walking through that residue, lying in it, and grooming it off their fur. That's worth thinking about.
What We Do Instead
Our mosquito control program is built around two services that take a fundamentally different approach.
Our barrier spray is an essential-oil-based formula that is EPA 25(b) exempt, an EPA designation meaning its active ingredients pose minimal risk to human health and the environment. It creates an effective mosquito barrier without broadcasting synthetic chemicals across your property.
Our high-impact traps disrupt mosquito reproduction and disseminate controls beyond your property line without broadcasting any dangerous pesticides into the environment. Rather than treating your entire yard with a broad-spectrum insecticide, these stations attract and eliminate mosquitoes before they start biting or breeding.
We employ both methods at the homes of customers who keep bees and the bees thrive. That's not a marketing claim. It's what we see in the field, season after season. When your treatment program is compatible with keeping a beehive in the same yard, you know you've found a better way to care for your yard.
The Bigger Picture
Your backyard is an ecosystem. There are insects you want gone and insects you need — pollinators that keep your garden productive, predators that keep other pest populations in balance, and organisms in the soil that keep your lawn healthy.
Our job is to make your yard comfortable for your family. Not to sterilize it.
We believe mosquito control should be precise, not broad-spectrum. It should solve the problem you hired us for without creating new ones. And it shouldn't require you to wonder what else it might be doing to your yard, your pets, or your family.
That's why we don't use pyrethrins. And that's why we built The Backyard Care Company around a different standard.
Ready for mosquito control that doesn't come at the expense of your backyard ecosystem? Get a quote and see what a different approach looks like.